Although Dooley typically doesn't want to run Medium sized items (since having many Smalls can ramp him faster), Atomic Clock is a powerful option worth building around.
This is because it has a 1.0 second cast time in combination with an effect that increases enemy cooldowns - two things Dooley loves, ramp and more time to ramp.
By combining Atomic Clock with a strong damage source alongside more speed and ways to disrupt your enemy, you have a potent Dooley build on your hands!
Overall, Atomic Clock has been pretty underrated. It takes up two crucial spaces that could go to Small items, and it does take some work to ramp up.
However, if you have ways to increase its ammo and ways to use Atomic Clock to create a burst damage engine, it can be incredibly powerful.
Ammo Increases
The challenging part of the build is finding ways to increase your Atomic Clock's default 3 Ammo. To have a viable 10 win build, you'll need it closer 5-6+ Ammo.
Finding Gunpowder will be your ideal way of increasing the Clock's capacity. As you go through PvE encounters, here are the options that can potentially drop Gunpowder:
Level 5 - Preening Duelist (700 HP)
Level 5 - Scount Trooper (750 HP)
Level 6 - Hakurvian Rocket Trooper (1000HP)
Another good way is by choosing the Scavenger Hunt option at level ups. This is particularly good with Dooley since he has a lot of Friends - you'll usually have at least one in your build.
The Core
The other necessary part of the Atomic Clock engine is a damage source to accelerate.
Although there might be other sources of primary damage you can substitute, The Core is something you can plan around from the start of your run.
This version of The Core also works particularly well because its cooldown gets lowered at Gold and Diamond rarities.
Supportive Items and Skills
To support the win condition of your main engine, you'll need speed ramp (Haste and Charge) and crowd control (Freeze and Slow). Here are some example options, but you can usually swap in other items and skills that fulfill similar roles.
Speed Ramp
Metronome
Since it doesn't have a wind-up time, the Metronome is an awesome catalyst to funnel your Atomic Clock's 1.0 second cast into.
In this build, we use Soldering Gun. While the Burn does help (it was 7 Burn, the final screen screenshot is bugged), the main purpose here is as a Multicast activator.
Soldering Gun
So in 1.0 second, the Atomic Clock bounces through the Metronome which accelerates the Soldering Gun into a Multicast which bounces back into the Atomic Clock.
Fiber Optics
Fiber Optics (placed leftmost) allows your Atomic Clock to ramp up two items at once, the Metronome and your damage source (placed rightmost).
What's great about Fiber Optics itself is that it can trigger from anywhere on your board, so it gives you the flexibility to move things and trigger more adjacent effects.
Tools of the Trade
Although Tools of the Trade seems ideal in a composition with many Tools, you can still get a lot of value out of it if you have one Tool that casts very fast. In this example's case, it's Smoldering Gun and Chris Army Knife.
Chris Army Knife is one of Dooley's best items in general right now since he's versatile - he can help support builds as a Friend, Weapon, and/or Tool.
Knife Tricks
If you can find it, Knife Tricks helps your engine ramp up in longer fights.
Crowd Control
While you speed up your own build, you can support your build by also slowing down your enemy's build.
Pierre's 5.0 second cast is very slow but the main part you want is its second effect, "When you use the Core, Freeze an item."
This gives your Core, which will already be casting quickly a way to also offer crowd control.
You can also look for skills like Sabotage and Stop That! to help disrupt your opponents.
Tips and Tricks
Besides PvE encounters that drop Gunpowder, you can also look for fights like Cosmic Roc which have drops that reduce your Cooldowns.
Curio is another great choice to find Cooldown Reduction.
If you aren't finding enough Ammo or ways to Upgrade your Core, it might be time to consider pivoting.
Reconfigure, which reduces your Tools cooldowns, is another good level up option besides Scavenger Hunt.
